Core temp only shows one temperature? Constantly

[tilyardinit]

Hi, I'm using intel duo core e8400 3.0 CPU.
I recently changed the case, and speed fan/core temp was working fine.
But now for some odd reason, the temperatures are just stuck. One is 37, the other is 40.
Even under full load after 10 minutes, the temps are the same...

Now the reason I changed the case was because of overheating and now I don't know weather it's to hot or not..

The BIOS in my other case said CPU was 67 Degree's, and now it says 30-31 degree's...

But would like to know why the temps are stuck with speed fan/real temp/core temp

 

[tilyardinit]

Oh, it went up to 41 degree's from 37, under full load...But this can't be right lol?